Sorry, the title might be a bit confusing: what I mean is, actors who have portrayed different comic/superhero characters in different films (as opposed to, say, Hugh Jackman reprising the Wolverine role in multiple films).
The examples I can think of off the top of my head so far:
Halle Berry: Storm (X-Men films) and Catwoman (Catwoman)
Keanu Reeves: John Constantine (Constantine) and, arguably, Neo (Matrix films)
Chris Evans: Johnny Storm (Fantastic 4 movies), Captain America (Avengers films)
Will Smith: Jay (Men in Black films), John Hancock (Hancock)
Kristy Swanson: Supergirl, Diana Palmer (The Phantom)
Ryan Reynolds (THREE different roles!): Hannibal King (Blade Trinity), Hal Jordan (Green Lantern), Wade Wilson (X-Men Origins: Wolverine)
Any others you can think of?
Here’s a sort-of: Ben Affleck is set to play Batman in the “Man of Steel” sequel. He also played George Reeves in “Hollywoodland” and wore the Superman suit.
Zoe Saldana - The Losers and Guardians of the Galaxy
Nicolas Cage - Ghostrider and Kick-Ass
Idris Elba - both Thor movies and The Losers
Ellen Page - X-Men: The Last Stand and Super
I was just reminded:
Michael Clark Duncan - Daredevil and Sin City
Jessica Alba - Sin City and Fantastic 4
Zoe Saldana. Uhura also appeared in comic-book form.
Benicio del Toro was in Sin City, the second Thor and will be in Guardians of the Galaxy.
Chris Pilgrim vs The World also features Brandon Routh and Chris Evans. Apparently Chris Evans was in “The Losers” as well. So, I’d say Chris Evans is the winner.
Aaron Taylor-Johnson: Kick-Ass (Kick-Ass), Quicksilver (Avengers: Age of Ultron)
Arnold Schwarzeneggar: Mr. Freeze (Batman & Robin), Conan (Conan the Barbarian, Conan the Destroyer)
Gary Oldman: Jim Gordon (Nolan’s Batman movies), Dr. Norton (RoboCop)
Well, there are several comics based on the character, but I don’t think it originated as one; same with G.I.Joe, Conan, and others, but I think if you have a character that gets his or her own comic series (as opposed to a limited series “movie adaptation” comic) it could count.
Also, the superhero bit opens up the possibility for non-comics superheroes, like Hancock.